Microcomputer systems were developed to study cardiovascular functions of avian embryos developing within the eggshell. The parameters to be measured were electrocardiogram (ECG), impedance-cardiogram (ICG), ballistocardiogram (BCG), acoustocardiogram (ACG), heart rate and arterial blood pressure of embryos and egg pressure. Measurements could be made without impeding adequate gas exchange through the eggshell and invading embryos.1. Chicken embryos (pre-pipped and externally pipped) and hatchlings were exposed to hypoxic and hyperoxic environments for 4 hours and their metabolic responses were investigated.2. Autonomic drugs were injected intravenously through a catheter, and responses of blood pressure and heart rate of chick embryos aging 12 to 18 days were studied.3. The apex-cardiogram was measured non-invasively using a piezo-electric film in newly hatched chicks and developmental patterns of heart rate during the 1-week were elucidated.4. Effects of installations of needle elect
… Morerodes (ECG and ICG) and microphone (ACG) upon measurements of embryonic heart rate were investigated in reference to BCG measurement.5. Tolerance of developing chick embryos to acute changes in ambient temperatures was elucidated non-invasively in reference to the heart rate.6. Two-dimensional cardiogenic ballistic movements of chicken eggs were investigated by recording trajectories of the ballistic displacement with a microcomputer system.7. Non-invasive long-term measuring system of embryonic heart rate was developed taking advantage of ACG signals and variability of the heart rate was shown during the last half of incubation.8. A new measuring system of egg BCG was developed using an electromagnetic induction coil and the BCG was recorded as a velocity of ballistic movements.9. Developmental patterns of embryonic heart rate and oxygen consumption in stored chicken eggs were investigated.10. Developmental patterns of embryonic heart rate in altricial birds, the pigeons and the bank swallow were studied. Less